Hello. I tried to draw some sprites with parallax. But the drawing order is front to back (with opengl in my original code, is back to front like painter's algorithm). Is posible a easy way to implement back to front with parallax or kos-pvr?

why not use the source of retrotap's firmware?
http://denki.world3.net/retro_v2.html

seems it can be ported to maple bus, yes, it can be ported "for the king, for the land, for the moountains"